When the initial concentration of a reactant is doubled in a reaction,its half-life period is not affected. The order of the reaction is:

Consider the following reaction,
$2H_{2(g)} + 2NO_{(g)} \rightarrow N_{2(g)} + 2H_2O_{(g)}$
which follows the mechanism given below:
$2NO_{(g)} \underset{k_{-1}}{\stackrel{k_1}{\rightleftharpoons}} N_2O_{2(g)}$ (fast equilibrium)
$N_2O_{2(g)} + H_{2(g)} \stackrel{k_2}{\rightarrow} N_2O_{(g)} + H_2O_{(g)}$ (slow reaction)
$N_2O_{(g)} + H_{2(g)} \stackrel{k_3}{\rightarrow} N_{2(g)} + H_2O_{(g)}$ (fast reaction)
The order of the reaction is

Define the following terms:
$(1)$ Rate law / Rate equation / Rate expression
$(2)$ Unimolecular reaction

For a chemical reaction,the rate law is $\text{rate} = k[A]^2[B]$. If $[A]$ is doubled at constant $[B]$,the rate of reaction:

The rate law for the reaction between substances $A$ and $B$ is given by $\text{Rate} = k[A]^n[B]^m$. If the concentration of $A$ is doubled and the concentration of $B$ is halved,what is the ratio of the new rate to the initial rate?

The order of a reaction can have: